Homo floresiensis gains in status

Scientists claim the skull of the human Homo floresiensis, referred to as the 'hobbit' proves it was a different species. The three-foot tall woman lived on the Indonesian island of Flores more than 13,000 years ago. An internal cast of the brain case proves that the hobbit's cranial features were intact and that it was not an ordinary person suffering from microcephaly, a disease that causes stunted growth and small brain size. It is now believed that this is a new human species.

For Professor Dean Falk of Florida State University in Tallahassee, the latest study confirms that the Flores skull belongs to a new species who was probably intelligent enough to make and use the tiny stone tools found alongside the bones. The volume of the hobbit's brain is only 417 cubic centimetres, about a third of the size of a normal adult. Sceptics have claimed that such a small brain would not be able to carry out the tasks of tool making and tool using associated with being human.

However, a team of scientists led by Professor Falk compared the internal cast of the hobbit's braincase with similar 'endocasts' of 10 normal, healthy people and nine people with microcephaly. The internal dimensions of the Hobbit's brain placed it clearly within the normal range of brains.

Moreover, it was found that the brain case has four unusual features that distinguish it from the brain cases of Homo sapiens, which suggests that its classification as a separate species - Homo floresiensis - is justified. This new combination of cranial features is unprecedented, and given the size, the smaller brain was therefore more complex.

Dating suggests that the hobbit lived on Flores for many tens of thousands of years and probably died out about 13,000 years ago, perhaps following a massive volcanic eruption. If Homo floresiensis is proven, and Professor Falk is correct, it would mean that a diminutive species of human being was living alongside Homo sapiens.

How the debate is unfolding

October 2004: A team of scientists from Indonesia and Australia announce the discovery of a skull and partial skeleton on the island of Flores. They say the bones belonged to a dwarf species of human being that they nickname 'the hobbit'. They classify it as a new species. November 2004: A rival scientist from Indonesia says the skull belongs to an anatomically modern human suffering from microcephaly. An acrimonious row occurs over the possession of the bones.

March 2005: Professor Dean Falk says that a brain scan of the hobbit's skull suggests the creature was capable of intelligent behaviour, and was not suffering from congenital brain disease.

October 2005: Australian scientists announce the discovery of more bones belonging to the hobbit. Crucially, they fail to find a second skull.

May 2006: Dean Falk's previous study is criticised for relying on a comparison with a microcephalic skull of a 10-year-old boy. June 2006: Dispute deepens. Some anthropologists claim that the stone tools found with the hobbit could only have been made by Homo sapiens. Others, however, claim that identical stone tools found a few miles away were made between 700,000 and 840,000 years ago, long before H. sapiens evolved.

August 2006: Critical scientists back up their claim that the hobbit is nothing more than a small-brained modern human.

January 2007: Dean Falk publishes "definitive" evidence showing Homo floresiensis should be recognised as a new species of dwarf human.